Chuck.



N. A. SHIGON. CHUCK.

APPLIOATION FILED FEB. 6, 1907.

Bymf.,

A TTOH/VE YS NATHAN A. sHIGoN, or NEW YORK, N. Y.

CHUCK.

Specification of Letters Patent.

Patented Jan. 7, 1908.

Application filed February 6. 1907. Serial No. 356.018.

To all whom it may concern.'

Be it known that I, NATHAN A. SHIGON, a citizen of the United States,and a resident of the city of New York, borough of Manhattan, in thecounty and State of New York, have invented a new and Improved Chuck, ofwhich the following is a full, clear, and exact description.

This invention relates to chucks designed especially for jewelers use,although capable of general application.

The primary purpose of the invention consists in providing a chuck withdetachable jaws having special clamping ends adapted to hold objects ofvarious shapes, and thereby enable the jaws most suitable for aparticular purpose to be applied to the chuck when desired, and removedat will to make place for others.

Other objects relating to the special construction and arrangement ofthe several parts will be understood from the following description andaccompanying drawings, in which drawings Figure 1 is a side elevation,partly in section, of a device embodying my invention; Fig. 2 is an endview of the device shown in Fig. 1; Fig. 3 is a vertical section takenon lthe line 3-3 of Fig. 1; Fig. 4 is a vertical section partly in sideelevation, of a device embodying a modification of my invention; Fig. 5is an end view of the device shown in Fig. 4; and Fig. 6 is an end viewof a chuck having a modified form of jaw.

As illustrated in the drawings, 1 represents a shank, partly plain andpartly threaded, having one of its ends 2 threaded to engage the head ofa lathe. The opposite end 3 of the shank is reduced and threaded so asto engage the head f1 of the chuck. A shoulder 5 is formed on one end ofthe shank adapted to receive set-screws 6 which also engage a flange 7formed on the head of the chuck, and thereby hold the head againstrotary motion on the shank. The head of the chuck is provided withrecesses inclined to the axial line of the head and the shank of thechuck, and ada ted to receive jaws 8 which are preferab y circular inoutline and have a sliding engagement with the recesses of the head. Thejaws when circular in outline are provided with longitudinal grooves 9adapted to receive the ends of set screws 10 which have a threadedengagement with the head of the chuck, and thereby prevent the jaws fromturning in their sockets.

-head of the chuck.

The rear ends of the jaws have a detachable engagement with a nut 11which is threaded interiorly to engage a thread l2 formed on the shankof the chuck. To this end the inner ends of the jaws are provided withrecesses 13 and lips 14 adapted to engage respectively an annular groove16 and flange 15 formed on said nut. The flange 15 is of smallerdiameter than thc body of the nut 11, so that while said flange engagesthe recesses 13 of the jaws of the chuck, t ie rear ends of said jawsbear against the forward face of the body of the nut. l/Vhen the jawsare inserted in the head of the chuck the rear ends of the jaws bearagainst the forward face of the nut, which moves the jaws inwardtogether, thereby keeping the recesses 13 in line with each other andwith said flange at all times and enabling said recesses to engage theflange 15 of the nut evenly and simultaneously. In grasping an object,moreover, the outward pressure on the rear end of the jaws is exerted bythe body of the nut, thereby enabling the body of the nut to take upsaid strain, while the flange 15 is used only for the purpose ofreti-acting the jaws in the The forward ends of the jaws are varied inconstruction in order to hold objects of different shape. As shown inFig. 1, the inner or clamping faces 17 of the jaws are beveled, so thatwhen said ends of the jaws are closed the faces thereof are in contactwith each other throughout their entire extent. A collar 18 is mountedupon the shank 1 and held thereon by means of a set screw 19, so as toenable the collar 1S to be moved along the shank, the nut 11 to beretracted from the ends of the jaws and the jaws to be removed from thehead when desired.

Instead of using j aws having clamping faces of the character shown inFigs. 1 and 2, the grasping surfaces of the jaws may be cut away on acircular line, as shown in Fig. 6, so as to grasp a larger object thancan' be held by the jaws shown in Figs. 1 and 2, and in addition to suchconstruction it is desirable to use jaws adapted to hold a spherical object. For this purpose the clamping ends of the jaws are made so as toflare outwardly, as indicated by the faces 2O of the jaws 21, shown inFig. 4, and curved longitudinally and transversely so as to attain afirm, even hold upon a spherical obj ect 22. In working sphericalobjects it frequently becomes necessary to bore a hole through theircenter.

The hole may iirst be bored half-way through the object, which may thenbe released from the jaws of the chuck and a center pin 23 I having areduced end 24, placed in a suitable aperture in the shank of the chuck.The drill may then be applied to the opposite side of the obj ect, whichis thereby automatically centered, and the remaining portion of the holedrilled in line with the preceding portion. Such a device is of specialvalue in drilling pearls and other objects of like character.

Other forms than those shown herein may obviously be applied to theclamping ends of the jaws if desired. Vhile in most instances I preferto make the jaws circular in outline, as already described and shown inFig. 1, they maybe made angular in cross section, as indicated by thejaws 2l of Fig. 4, without departing from my invention. In such casesthe jaws are held against rotary movement on the head of the chuckbecause of their shape, and the recesses 9 and engaging set screws 1()used with cylindrical jaws are not required.

I do not desire to be limited to the specific construction orarrangement of vthe respective parts by which the rear ends of the jawsare held in engagement with the nut 11. Other means having similarcapabilities may be used without departing from my invention.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent is A chuck comprising a shank, a head mountedthereon and provided with inclined sockets, jaws slidingly mounted insaid socl ets, inclined to the axial line of said shank and provided onthe inner sides of their rear ends with recesses, and a nut having athreaded engagement with said shank adapted to bear with its faceagainst the end of said jaws, and provided with a flange smaller indiameter than that of the body of the nut, ofi-set from s aid body, andadapted to engage the recesses of said jaws.

In testimony whereof l have signed my name to this specication in thepresence of two subscribing witnesses.

NATHAN A. SHIGON.

Vitnesses:

ROBERT W. HARDIE, JNO. M. RITTER.

